Lead wire feeding device



Feb. 17, 1959 P. w. MAURER ETAL LEAD WIRE FEEDING DEVICE 2 Sheets-Sheet1 Filed Sept. 26, 1957 INVENTORS PIE/F1?! 0141144045? 6 HEA/m Z.5.44/57- P. W. MAURER ET AL LEAD WIRE FEEDING DEVICE Feb. 17, 1959 2Sheets-Sheet 2 Filed Sept. 26, 195? 11v VEN T0125 P/E/FAE 144/144 0mm 5HENRY A. 5.4 057' By a A 7- TUBA/5) United States Patent LEAD WIREFEEDING DEVICE Pierre W. Maurer, Nutley, and Henry L. Blust, Lyndhurst,N. J assignors to Radio Corporation of America, a corporation ofDelaware I Application September 26, 1957, Serial No. 686,332

7 Claims. (Cl. 193-2) This invention relates to apparatus for handlingwire members and particularly to apparatus for feeding a plurality ofpredetermined length lead-in wires to a stem mold in the fabrication ofbutton-type electron tube stems.

In the manufacture of certain electron tubes, a button type stemstructure is prefabricated for subsequent sealing to a tubular glassmember to provide an electron tube envelope. Such a stem structure maycomprise a glass disk with a plurality of wires sealed therethrough in acircular boundary. Fabrication of such a stem is performed on a turrettype machine having a plurality of stations positioned around andadjacent the periphery thereof. At one station the plurality of shortlength leadin wires is deposited on a mold onto which is subsequentlyplaced a cylindrical glass member to be formed into the aforementioneddisk. The several lead-in wires are dropped by a separate wire handlingdevice into a member having a plurality of tapered chutes which directthe wires upon the mold. However, in prior art lead wire feedingdevices, much difficulty has been encountered due to jamming ofdistorted lead wires in the chutes. Such jamming results in the entiremachine having to be shut down to clean out the jammed wires thusgreatly reducing the stem machine efficiency.

It is therefore an object of our invention to provide improved lead wirefeeding apparatus which is not subject to the aforementioned jammingproblem of the prior art.

Generally, according to our invention, apparatus for feeding lead wirescomprises a longitudinally slotted frustoconical core seated in a matingcore housing. A plurality of chutes are thus provided for directing leadwires inserted therein onto a mold. The core housing member is splitsuch that the split portions thereof can be pivoted away from theslotted core to effectively open the sides of the chutes thus permittingany distorted wires which might be jammed therein to fall free.

In the drawings:

Fig. l is a side elevation partly in cross section of lead wire feedingapparatus according to our invention;

Fig. 2 is a cross sectional View taken along line 2-2 of Fig. 1;

Fig. 3 is an exploded perspective view of the chute and split nozzleportions of the apparatus of Fig. 1;

Fig. 4 is a side elevation view of the plunger assembly disposed belowthe lead wire feeder and adapted for ice cooperation therewith. Althoughshown in proper relative disposition, for the sake of simplicity ofdescription, no inner-connecting mounting means of the aforementionedapparatus is shown. In operation, the turret table 16 is fixedly mountedin a vertical orientation but is adapted for rotation about a centralvertical axis 17 as indicated by the arrow; the plunger assembly 14 ismounted in a fixed position; and the chute-and-nozzle assembly 12 isfixedly mounted laterally but is adapted for vertical movement upwardagainst the plunger assembly 14 and downward into seating relationshipwith a mold jig 18 as indicated by the arrows. Figs. 2, 3, and 4 inconjunction with Fig. 1 best show the detail assembly of thechute-and-nozzle and plunger assemblies according to our invention.

In Fig. 3 the chute-and-nozzle assembly 12 is shown in explodedperspective to include a slotted frusto-conical core 26 adapted to besupported by means such as a first core housing 22 and seated in asecond core housing or split housing 24. For the sake of'clarity andbrevity these housing members will hereinafter be referred torespectively as simply the core housing 22 and the nozzle housing 24.With the slotted core 20 seated therein, a plurality of tapered chutes26 are thus provided. These are best shown in Figs. 1 and 2. As such,one wall portion 28 of each chute 26 is provided by the inner walls ofthe core housing 22 and the nozzle housing 24. The slotted 20 isdimensioned to seat in the core housing 22 and in the nozzle housing 24with the large end 30 of the core 20 flush with the corresponding end ofthe core housing 22 and with the small end 32 of the core 20 slightlyrecessed within the nozzle housing 24, as shown in Fig. 1. A top cap 34is provided which has a series of apertures 36 therethrough, with eachaperture aligned with one of the slots 38 of the core. The cap 34 isadapted to be attached to the slotted core 20 by a machine screw 40; andthe slotted core 20 is in turn fixed in the core housing 22 by a setscrew 42.

The split nozzle housing 24 comprises two similar mating nozzle pieces44 each including a flat plate portion 46 and an internally tapered corereceiving portion 48. Each nozzle piece 44 is pivotally attached to thecore housing 22. by a screw 50. Each of the two nozzle pieces 44 carriesa peg 52 at the end opposite its screw 50 to which one end of a coilspring 54 is connected. The coil spring 54 urges the nozzle pieces 44toward each other and around the end portion of the slotted core 20.Thus, the core receiving portions 48 of the nozzle pieces 44 serve as acontinuation of the core housing 22 to provide a continuation of thechutes 26. The plate portions 46 of the nozzle pieces 44 are cut away attheir inner adjacent edges 55 next to their mounting screws 50. Thisenables the nozzle pieces 44 to be spread apart by pivotal motion abouttheir mounting screws 50. Also, in order toprovide clearance for thepivotal movement, either the side of the core 26 facing the pivot screws50 or the inner corners 56 (Fig. 5) of the nozzle pieces '44 in contacttherewith, must be cut away. This is necessary since the corners 56 ofthe nozzle pieces 44, in being pivoted away from the core, first moveslightly into the core. This is'caused by the fact that the pivots 50and the corners 56 are not on the same radial line of the core 20. Figs.1, 3 and 5 show the core 20 with a cut-away portion 57 where the corners56 of the nozzle pieces 44 would otherwise contact. Alternatively, ofcourse, the corners 56 themselves could be beveled off. The plateportions 46 are also provided with a V-bevel 58 at their contiguousedges on their upper surfaces of the other end thereof for cooperationwith the plunger assembly apparatus 14 as will hereinafter be described.The extending'en'd of the core receiving portions 48 of the nozzlehousing 24 is provided with a slight counterbore 62 to enable a seatingindexing with the mold jigs 18 on the turret table.

In Figs. 1 and 4, the plunger assembly 14 is shown to comprise a wedgeplunger 62 having a V-nose 64 which is longitudinally slidable in aplunger housing 66. A first pin 68 is attached to the upper end 70 ofthe wedge plunger 62 and a second pin 72 is attached to the lower end 74of the plunger housing 66. A coil spring 76 connected between the twopins urges the wedge plunger 64 downward to where a stop-ledge 78 on theupper end thereof contacts the plunger housing 66.

In the fabrication of a button stem the entire chuteand-nozzle assembly12 is first lowered down upon one of the mold jigs .18 indexedtherebeneath such that the mold jig is situated in the counter-bore 62of the nozzle housing 24. A lead wire dispensing device (not shown) thenplaces one wire in each of the apertures 36 of the top plate 34- of thelead wire feeder 10 where they are free to fall down the chutes 26 andonto the mold jig in a spreading apart of the nozzle pieces 44 from eachother. At this point the chutes 26 have been opened to permit anydistorted lead wires which might have been placed therein to be ejected,thus preventing jamming during the succeeding wire feeding operation.The opening clearance afforded between the core 20 and the nozzle pieces44 is best illustrated by Fig. as shown in solid lines. By contrast, aclosed position of the nozzle pieces 454 is shown in phantom in the samefigure. The resistance to spreading of the nozzle pieces 44 by the coilspring 54 attached thereto is less than the resistance provided by thecoil spring 76 to an upward slidable movement of the wedge plunger 64.This results in the nozzle pieces 44 spreading away from the slottedcore 20 rather than the wedge plunger sliding within its housing.However, the spring biased slidable operation of the wedge plungerserves as a safety measure against machine damage should the nozzlepieces 44 be frozen against pivotable movement.

With reference to Figs. 1-5, our invention has been described andillustrated as applied to the production of button-type stems as used inthe fabrication of the conventional seven-pin miniature electron tube.Although our invention proves most advantageous in such an ap plicationas this, where relatively fine, easily distortable lead-in wires areused, it nevertheless is not limited to the specific form illustrated.

Fig. 6 illustrates a modified embodiment of the split nozzle portion ofour invention which is better suited for production of 8 pins stems.Also, an alternative means of providing the pivotal movement to thenozzle pieces is illustrated.

A single pivot split nozzle 80 of Fig. 6 might simply be substituted forthe split nozzle 24 of Figs. 1 and 3. Like its counterpart, the splitnozzle 80 is adapted to receive the lower end of a slottedfrusto-conical core 90 and to be pivotally removed therefrom. The splitnozzle 80 comprises two nozzle pieces 82 and 83 which are pivotallymounted in a split bearing arrangement 84 about a single pivot screw 86.Since the pivot 86 lies on the split line 88 of the two nozzle pieces 82and 83, the clearance problem of the split nozzle assembly 24 discussedin reference to Fig. 5 is non-existent. Thus, neither the core 90 northe corners 92 of the nozzle pieces 82 and 83 needbe cut away. As such,the single pivot nozzle 80 is better suited for production of stemdesigns where a lead-in chute 94 must be provided at the point where thenozzle piece corners 92 contact the core 90.

Each of the nozzle pieces 82 and 83 is provided with an arm 96. The arm96 of one nozzle piece carries an arcuate cylinder 98, and the arm 96 ofthe other nozzle piece carries a coperating piston 100. A coil spring102 urging the nozzle pieces 32 and 83 together is stretched between thetwo arms 96. A source of air pressure (not shown) can be connected tothe cylinder 98 for providing a means of spreading the nozzle pieces 82away from the core 90.

It will be appreciated that either the single pivot nozzle apparatus orthe piston-cylinder apparatus 98100 can be independently incorporated asa portion of our lead wire feeder invention.

For purposes of simplicity of description, our invention has beenillustrated in two of its simplest forms. In actual practice however,various design features might be modified in order to better adapt ourinvention to specific turret machine apparatus. General shape of theconstituent parts and specific assembly thereof can be modified withoutdeparting from the scope of the invention. For example, in one specificapplication, in order to provide easy assembly and disassembly, it hasbeen found expedient to divide the chute-and-nozzle assembly of Fig. 1into two separate sections generally along the horizontal planecontaining'the section line 2-2 as shown in Fig. 1. The separatesections are then assembled with a tongue and groove arrangement.

Other modifications will be readily suggested to one skilled in the artwithout departing from the spirit of our invention.

We claim:

1. A lead-in wire feeder comprising an elongated core having a pluralityof longitudinal slots around the peripheral surface thereof, meanssupporting said core, and a housing receiving said core, said housingbeing split into two parts along a plane generally longitudinal to saidcore, each part being pivotally mounted relative to said core forpivotal movement away from said core.

2. Lead wire feeding apparatus comprising a generally frusto-conicalcore longitudinally slotted around the peripheral surface thereof; meanssupporting said core; a housing member dimensioned to receive said core,said housing member being divided into two pieces along a longitudinaldiametric plane of said core, said housing pieces being pivotallymounted relative to said core and adapted to be pivoted away from saidcore; and means for effecting pivotal movement of said housing pieces.

3. Wire handling apparatus comprising a frusto-conical core having aplurality of tapered longitudinal slots around the periphery thereof,first means supporting said core, a pair of housing members abuttingeach other along a plane of abutment and each having a semifrustoconical recess therein, corresponding parts of said recessesfacing each other and constituting a frusto-conical cavity adapted toreceive said core in seatable relationship, said housing members beingpivotally mounted relative to said core for movement away from saidcore, and second means for effecting said movement.

4. Wire handling apparatus according to claim 3 wherein said secondmeans comprises a wedge plunger adapted to contact said housing membersat their plane of abutment and to spread said members apart.

5. Wire handling apparatus according to claim 3 wherein said secondmeans comprises an air piston-and-cylinnozzle housing member and adaptedfor insertion be tween said nozzle housing portions to effect saidarcuate movement.

7. Apparatus for handling wire lengths comprising a spring biased wedgeplunger and a chute-and-nozzle assembly mounted adjacent thereto andmovably adapted for engagement therewith, said chute-and-nozzle assemblyincluding a frusto-conical core having a plurality of longitudinal slotsdisposed around the periphery thereof, a core housing having a taperedaperture therethrough seatably receiving said core, a nozzle housinghaving a 10 ment.

No references cited.

